Tripod-head for photographic instruments.



PATBNTED MAY 26, 1903.

No. 729,520. y

' P. A. ROBBINS.

TRIPOD HEAD POR PHOTOGRAPHIC INSTRUMENTS.

ABPLIUATION FILED MAY l2. 1902.

Ho MODEL.

L. "vv

nio. 729,520.

IINTTnn vSTnTns menten may 26, 1903.

PATENT @Tricia FRANK A. ROBBINS, OF WORCESTER, MASSACHUSETTS.

raison-Heli D FOR PHOTOGRAPH-HC INSTRUMENTS.

SPECIFICATION forming part of Letters Patent No.-72v9,520, dated May 26, 1903.

Application filed May 12, 1902 To a/ZZ/ '.u/towb it may concern:

Be i-t known that I, FRANK A. RoBBiNs, of the city and county of \Vorcester and State of Massachusetts, have invented certain new and useful Improvements in Tripod-Heads for Photographic Instruments; and I do hereby declare that the following `exact description thereof, reference being had to the accompanying drawings, forminga part 1o of this specification, and in which- Figure l represents a photographic viewcauiera set upon a tripod having a head em bodyingmyimprovemeuis. Fig? represents, upon an enlarged scale, a side view of said improved tripod-head', and Fig. 3 represents, upon the same enlarged scale as Fig. 2, a central vertical section through the parts shown in Fig. 2, with the swivel camera-support shown in different positions by full and dotzo ted lines.

The object of my invention is to provide a tripod-head for photographic Ainstruments whereby the instru mf-nt may be leveled independent of the tripod and it consists in proriding the usual head, to which the tripodlegs are attached, with an adjustable swivel device upon which the instrument is mounted, as will be hereinafter more fully set forth.

To enable others to better understandthe o nature and purpose of my said invention, I

will now proceed to describe it more in detail with reference to the accompanying drawings.

- In said drawings, A represents the tripod- 5 head, B B B the legs which support the same,

and C a photographic camera which is mounted on said head. As my invention relates only to the tripod-head, the following description will be confined thereto. It is adapted 4o to be used with any style or shape of legs and for supporting any kind of photographic camera or instrument. Said tripod-head is constructed as follows: The base-plate a,

to which the upper ends of the legs B are attached, is provided with the central halfsphere-shaped socket b in its upper side, in

which a ball c is adapted to fit, and over said ball is fitted a holding-plate d, having a concavity e in its 'under side, which ts the 5o upper surface of the ball. It also has a central vvertical opening to receive .the vertical from ball c and upon post g, entending up is a full, clear, and

serai No. 106.865. oto maar l whose upperend is mounted the disk or plate h, which'its against and forms a supportingbed for the camera C when the latter is vmounted on the head. Said disk or plate h is preferably made of composition material and may be of any desired shape. Under said disk or plate is also preferably employed a metal plate 7L', fastened to the upper disk or plate and having a central hub h2, provided with a vertical opening to receive the screw end of post g, asis shown in the drawings. The screw end of the post extends a little above disk or plate h, as is shown in the drawings, to admit of the camera being screwed thereon. The plate d is fastened to the usual tripod-head or base-plate a in any suitable and convenient manner. In this instance it is shown as being fastened by means ofthe screws it; but I do not limit myself thereto, as numerous ways may be adopted to accomplish the saine purpose parting from the scope of my invention. A vertical threaded opening is formed in the bottom of plate A, central with the spherical concavity formed therein, as previously described, and in said threaded opening is fitted a thumb-screw j, whose inner end is ladapted to bear against the surface of ball c. Therefore with said ball fitted between the two concavities b and e in the plates a and d, respectively,as previously described and shown in the drawings, it is obvious that when the thumb-screw j is turned in it presses longitudinally against the spherical surface of the ball and clamps it between said end and the inner surface of the plate d to hold said ball and the parts mounted thereon rigid, 'and when said thumb-screw is turned out the ball is released, so that it may turn in its bearings. To facilitate holding the ball more securely, the inner end of the thumb-screw j is preferably provided withaheadj' and made concave in shape to fit the convex surface of the ball, and thereby produce a greater frictional holdin g-surface thereon. The ball is tted loose in its bearings, so thatit may easily turn when not held by the thumb-screw, as aforesaid. Said head j'. may be made integral with the post, as shown, or separate therefrom, as desired. The post g,extending upward from ball c, is provided with a threaded upper end to t v'thensual threaded opening in the bottom of without de- C. Said post may also be provided between said threaded end and the ball c with a milled coiiar is, whereby the operation of tnrning said threaded upper end into the opening in the camera may be facilitated. l do not liinit myself thereto, however, as it is not an essential feature of my invention.

it Wili be apparent from the foregoing description and by reference to the drawings that a camere mounted on my improved tripod-head may be adjusted to a level position entirelyindependent of the level of the usual tripod-heed (corresponding to the base-plate a) and of the positions of the legs of the tripod-as, for instance, the tripod may be seiI up in any position approximately level with.- ont thought to the leveling of the photograph ing instrument, even With the base-plate a considerably ont of level, as is shown in. Fig.

l, and said instrument afterward adjusted in convenient and expeditious manner to a perfectly level position. rlhose using photogra phic instru ments, especially in outdoor or field work, will readily appreciate the advantages thereby derived in the saving of time and trouble over the present method nsnaliy required of leveling said instrument byadjnsting one leg and then another of the tripod to bring the head to a level. My invention is of especiai advantage for the use of amateur photographers and in leveling the camera upon uneven or rocky ground.

My improved device is simple in `construcion end, as above stated, easii and quickly neenipnlated and adds hut little to the cost or" the usual tripodheads having no independent means of adjustment. Said device may be need upon a metal base-plate or head a, provided with the nenni holding-ears Z, projecting from its under side, to which the legs are attached, es is shown in the drawings, or

said device may be attached to any tripodhead to which parting from the principle of my invention.

While my invention is designed principally for photographic instruments, as previously described, it is equally applicable for engineers levels and other instruments, and I therefore do not limit the application thereof to saiduse.

Having now described my invention, what l' claim therein as new, and desire to secure by Letters Patent, is-

In a tripod,- the base-plate a, having the socket b in its upper side and a central, vertical threaded opening at the bottom, also having the ears Z projecting from its under side and a central, vertical opening` at the top, means for fastening said plate d to plate a end thulnb-screwj fitted to turn in the central, vertical, threaded, bottom opening in base-plate o, and Whose inner end is adapted to bear against ball c, in combination with said hall c, the post g, extending up therefrom through collar 7L', said collar h', mounted on said post near its upper end, horizontal top plate h, arranged above said collar and having a central, vertical opening to receive post g, said post being threaded at its upper end and extended a short distance above said plate h, and means for fastening the collar h to plate h, substantially as set forth and shown.

FRANK A. ROBBINS.

Witnesses:

A. A. BARKER, W. 13. Nonnen.

it may be adapted Without de'- 1 

